So I brewed a batch of O Flannagan's stout on Saturday & fermented with a packet of Nottingham. It took about 36 hours to show any signs of krausen or airlock bubbling, and the krausen only lasted a day and didn't get more than an inch high. I was kind of afraid I had a bad pack of yeast, so I took a sample today and the SG is down to 1.016 from 1.043 (I overshot my volumes a bit). This is just my fifth batch, but all of my others have had really thick krausen and very vigorous fermentations, so I was wondering what was different this time. Is this normal for this yeast? Is it because of a slightly lower OG? This is also the darkest beer I've done so far, could that be the difference?

The beer already tastes good, so I'm not worried about it, just looking to fill in my understanding a bit.

There's been several threads about a bad batch of Nottingham that acts this way, but I've had a few batches that do exactly what you describe with "good" Nottingham. So far it's been 3 batches that I used irish moss in. Coincidence? Don't know. My beer tastes, looks, and smells good though so I'm not worried either. Haven't seen an explanation yet.

Same here. Usually my blowoff tube needs a good clean after the fermentation but this time only got an inch and a half. Fermented out though. I guess when you isuLly gt firework you come to expect them... They are exciting!

Ever consider that it could be the particular brew you are fermenting? I made a big starter using Wyeast Irish Ale yeast, pitched half into a red ale, and the other half was pitched into a Scottish wee heavy, the heavy was blowing off in 12 hours, the red had an inch and a half of krausen on it for the duration of fermentation, I decanted and measured the yeast evenly into the carboys, both fermenters were in the same fermentation fridge at the same temp, and the stick on fermometers were both reading the same temp prior to pitching. odd thing is the last time I made the red, I pitched the same amount of Irish ale yeast, and it was blowing off in 10 hours.

Fermentation is a dynamic process involving living organisms, I have never had fermentation react the exact same way twice in a row, too many variables to contend with. I hit the same efficiency almost every time, I pitch proper quantities of yeast, and I ferment in a controlled environment.

I use Notty on many brews, some react violently, some putter along with hardly a blip of the airlock, no logic to the way it reacts, even using a washed cake from a violent fermentation, next batch might seem to move in slow motion, but another vial of the same yeast cake will blow off in a couple hours.

Very intersting, azscoob. I think I was particularly surprised because I read in a thread recently that flaked barley tends to result in more intense krausen/blowoffs, and this is the first time I've used it. Like I said, I'm not worried, just curious.

Bradmont, my main reason for posting that windy response is that too often folks leap to the "I got bad Notty" response, I understand that there were a couple issues with some lot numbers, and those have been resolved, but it seemed that there were a lot of posts along the lines of I have no bubbling yet, its been 24 hours so I think I got a bad packet, that just promotes the thought that Notty is just a crap product and shouldn't be trusted. I have seen many knee jerk reactions that are too quick to blame the yeast, and not to look into other issues or processes that may cause a delayed or stalled fermentation or off flavors etc...

I am glad you were looking into if there are connections to beer style, Original gravity, and ingredients relating to fermentation vigor, rather than the easy route of blaming the Notty.